Lung Cancer Proteogenomics: Shaping the Future of Clinical Investigation.

BACKGROUND: Lung cancer is associated with a high incidence of mortality worldwide. Molecular mechanisms governing the disease have been explored by genomic studies; however, several aspects remain elusive. The integration of genomic profiling with in-depth proteomic profiling has introduced a new dimension to lung cancer research, termed proteogenomics. The aim of this review article was to investigate proteogenomic approaches in lung cancer, focusing on how elucidation of proteogenomic features can evoke tangible clinical outcomes. METHODS: A strict methodological approach was adopted for study selection and key article features included molecular attributes, tumor biomarkers, and major hallmarks involved in oncogenesis. RESULTS: As a consensus, in all studies it becomes evident that proteogenomics is anticipated to fill significant knowledge gaps and assist in the discovery of novel treatment options. Genomic profiling unravels patient driver mutations, and exploration of downstream effects uncovers great variability in transcript and protein correlation. Also, emphasis is placed on defining proteogenomic traits of tumors of major histological classes, generating a diverse portrait of predictive markers and druggable targets. CONCLUSIONS: An up-to-date synthesis of landmark lung cancer proteogenomic studies is herein provided, underpinning the importance of proteogenomics in the landscape of personalized medicine for combating lung cancer.

Immunotherapy in Cervical and Endometrial Cancer: Current Landscape and Future Directions.

Gynecological cancers pose a significant burden on women's health worldwide, necessitating innovative treatment approaches. Immunotherapy has emerged as a promising strategy, harnessing the body's immune system to combat cancer. This review aims to provide a comprehensive overview of the current landscape and future directions of immunotherapy in cervical and endometrial cancer. Methods: A thorough literature search was conducted to identify relevant studies and clinical trials. The main methods and treatments employed in immunotherapy for cervical and endometrial cancer, including immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapies, are briefly described. Results: Immune checkpoint inhibitors, such as anti-PD-1/PD-L1 antibodies, have shown remarkable clinical efficacy in certain gynecological malignancies, particularly in advanced or recurrent cases. Additionally, ongoing research on cancer vaccines and adoptive cell therapies holds promise for personalized and targeted treatment options.

Weight gain, gender, and antipsychotics: a disproportionality analysis of the FDA Adverse Event Reporting System database (FAERS).

INTRODUCTION: Side effects are a very important aspect of antipsychotic treatments. Weight gain is an important side effect that jeopardizes the uninterrupted therapy administration, especially in patients with psychiatric conditions. This case-non-case pharmacovigilance study aims at investigating in a real-world adverse event reporting system whether several antipsychotics increase the risk of weight gain reporting, and the differences among men and women as far as weight gain as a reported adverse event is concerned. AREAS COVERED: Adverse event reports submitted to the FDA Adverse Event Reporting System of the Food and Drug Administration of the United States (FAERS) of 24 major antipsychotics were extracted, cleaned, and analyzed to determine which of these drugs were correlated with weight gain. The Reported Odds Ratio (ROR) and the adjusted Reported Odds Ratio (aROR) were calculated for each antipsychotic using logistic regression models. Demographics like age, gender, and concomitant insulin use were taken into consideration for each drug. EXPERT OPINION: Women had a statistically significant increase in weight gain reporting compared to men, while the men's group was associated with a reduced weight gain reporting in every antipsychotics in the logistic regression analyses. Out of the 24 antipsychotics included in our analysis, Aripiprazole, Brexpiprazole, Olanzapine, and Haloperidol had statistically significantly more weight increase reporting compared to the others.

Pharmacologic Stewardship in a Rural Community Pharmacy.

BACKGROUND: Pharmacotherapy is an essential part of patient care. In order to achieve optimal health outcomes, safe and effective prescribing and administering of medications is crucial, especially since the process of pharmacotherapy can cause serious problems, mainly adverse events and/or interactions, that often pass undetected. OBJECTIVE(S): To investigate the feasibility of using community pharmacies as checkpoints to detect errors and failures in prescribing, as well as patients' compliance with pharmacotherapy. To this end, analysis and recording of the prescribing process was carried out and error-prone points were identified. METHODS: Patients and caregivers filling prescriptions during the first 4 weeks of November 2017 and February 2018 answered questions in order to evaluate their attendance of regular checkups and their compliance with prescribing instructions. All prescriptions filled at the pharmacy were examined for detection of prescription errors and drug-drug interactions. Statistical analyses, including calculations of the correlation coefficient phi (φ), chi-square, and confidence intervals, were carried out. Detected errors and failures were evaluated by application of the Health Failure Mode Effect Analysis (HFMEA) quality tool. RESULTS: A significant number of patients (16.7%) failed to regularly attend checkups regarding known health problems (95% CI: 10.6-22.7%), a corresponding percentage (16%, 95% CI: 10.1-21.9%) did not comply with prescribed pharmacotherapy, and a significant proportion of patients self-medicated regularly (32%, 95% CI: 24.5-39.5%). A total of 8.6% of prescriptions included medication combinations with a potential for severe drug-drug interactions (95% CI: 7.1-10.2%) while 58.7% of the prescriptions included combinations that could lead to moderate ones (95% CI: 56.1-61.4). The HFMEA indicated that all problems recorded required immediate interventions, except for prescribing errors. CONCLUSIONS: Community pharmacies can be potential checkpoints for the detection and evaluation of prescribing errors and pharmacotherapy failures.

Egg White and Yolk Protein Atlas: New Protein Insights of a Global Landmark Food.

(1) Background: The chicken egg is an animal product of great agronomic interest. The egg white and yolk constitute high-quality protein sources for humans with high digestibility and well-balanced amino acid profiles. Despite the egg white and yolk protein's undisputed value, research to unravel their full proteome content and its properties is still ongoing. We aimed to exhaustively analyze the proteome of egg white and yolk by applying intrinsic proteomics and bioinformatics approaches in order to unravel the full protein potential of this landmark food. (2) Methods: A total of 45 freshly laid, unfertilized, chicken eggs were subjected to nanoLC-MS/MS Orbitrap analysis following a peptide pre-fractionation step. A comprehensive bioinformatics processing step was undertaken towards elucidating potential activities and roles of identified molecules. In parallel, the literature was mined concerning all reported egg white and yolk protein identifications. (3) Results: Our analysis revealed 371 and 428 new proteins, reported for the first time to be present in the egg white and yolk, respectively. From the bioactivity standpoint, egg white and yolk proteins showed high enrichment for antioxidant and anti-inflammatory processes, while exerting high relevance for the apoptosis and focal adhesion pathways. (4) Conclusions: Egg white and yolk proteins exert diverse and multifaceted properties. A total of 799 proteins were reported for the first time as being part of the egg and yolk. Our novel protein data enriched those already published in the literature and the first ever chicken egg white and yolk Protein Atlas, comprising 1392 protein entries, was generated. This dataset will provide a cornerstone reference for future studies involving egg proteins.

Tumor Markers and Their Diagnostic Significance in Ovarian Cancer.

Ovarian cancer (OC) is characterized by silent progression and late-stage diagnosis. It is critical to detect and accurately diagnose the disease early to improve survival rates. Tumor markers have emerged as valuable tools in the diagnosis and management of OC, offering non-invasive and cost-effective options for screening, monitoring, and prognosis. PURPOSE: This paper explores the diagnostic importance of various tumor markers including CA-125, CA15-3, CA 19-9, HE4,hCG, inhibin, AFP, and LDH, and their impact on disease monitoring and treatment response assessment. METHODS: Article searches were performed on PubMed, Scopus, and Google Scholar. Keywords used for the searching process were "Ovarian cancer", "Cancer biomarkers", "Early detection", "Cancer diagnosis", "CA-125","CA 15-3","CA 19-9", "HE4","hCG", "inhibin", "AFP", "LDH", and others. RESULTS: HE4, when combined with CA-125, shows improved sensitivity and specificity, particularly in early-stage detection. Additionally, hCG holds promise as a prognostic marker, aiding treatment response prediction and outcome assessment. Novel markers like microRNAs, DNA methylation patterns, and circulating tumor cells offer potential for enhanced diagnostic accuracy and personalized management. Integrating these markers into a comprehensive panel may improve sensitivity and specificity in ovarian cancer diagnosis. However, careful interpretation of tumor marker results is necessary, considering factors such as age, menopausal status, and comorbidities. Further research is needed to validate and refine diagnostic algorithms, optimizing the clinical significance of tumor markers in ovarian cancer management. In conclusion, tumor markers such as CA-125, CA15-3, CA 19-9, HE4, and hCG provide valuable insights into ovarian cancer diagnosis, monitoring, and prognosis, with the potential to enhance early detection.

Vitamin Effects in Primary Dysmenorrhea.

BACKGROUND: Primary dysmenorrhea is considered to be one of the most common gynecological complaints, affecting women's daily activities and social life. The severity of dysmenorrhea varies among women, and its management is of high importance for them. Given that non-steroidal anti-inflammatory drugs (NSAIDs), the established treatment for dysmenorrhea, are associated with many adverse events, alternative therapeutic options are under evaluation. Emerging evidence correlates management of dysmenorrhea with micronutrients, especially vitamins. PURPOSE: The aim of this narrative review is to highlight and provide evidence of the potential benefits of vitamins for the management of dysmenorrhea. METHODS: The articles were searched on PubMed, Scopus and Google Scholar. The searching process was based on keywords, such as "primary dysmenorrhea", "vitamins", "supplementation", "vitamin D", "vitamin E" and others. Our search focused on data derived from clinical trials, published only during the last decade (older articles were excluded). RESULTS: In this review, 13 clinical trials were investigated. Most of them supported the anti-inflammatory, antioxidant and analgesic properties of vitamins. Particularly, vitamins D and E revealed a desirable effect on dysmenorrhea relief Conclusion: Despite the scarcity and heterogeneity of related research, the studies indicate a role of vitamins for the management of primary dysmenorrhea, proposing that they should be considered as alternative therapeutic candidates for clinical use. Nevertheless, this correlation warrants further research.

Biopharmaceuticals against substance use disorders - Present and future.

BACKGROUND AND OBJECTIVES: Pharmacological treatments available for substance use disorder (SUD) focus on pharmacodynamics, agonizing or antagonizing the drug of abuse (DOA) on receptor level. Drawbacks of this approach include the reliance on long-term patient compliance, on-target off-site effects, perpetuation of addiction and unavailability for many DOAs. Newer, pharmacokinetic approaches are needed that restrict DOA's access to the brain or disrupt DOA-instated brain changes maintaining addiction. Biotechnology might be able to provide the right biopharmaceutical tools to deliver a fine-tuned solution with less side effects compared to currently available treatments. METHODS: This review examines the available literature on biopharmaceuticals developed to treat SUD. RESULTS: Active and passive immunization, metabolic enhancers that augment DOA metabolism and clearance, as well as genetic/epigenetic modulation are promising next generation SUD treatments. Active immunization relies on production of antidrug antibodies by means of vaccination, while passive immunization constitutes of exogenous administration of such antibodies. Metabolic enhancers include drug-specific metabolizing enzymes that can be administered or secreted by modified skin grafts, as well as catalytic antibodies that hasten DOA metabolism. Nanotechnological advances can also allow for brain delivery of siRNAs, mRNAs or DNA in order to modulate central, common in all addictions, genetic or epigenetic targets attenuating drug seeking behavior and reversing drug-induced brain changes. CONCLUSIONS: and Scientific Significance: Biopharmaceuticals can in the future complement or even replace traditional pharmacodynamics approaches in SUD treatment. While passive and active immunization biopharmaceuticals have entered human clinical trials, metabolic enhancers and genetic approaches are at the preclinical level.

mRNA in the Context of Protein Replacement Therapy.

Protein replacement therapy is an umbrella term used for medical treatments that aim to substitute or replenish specific protein deficiencies that result either from the protein being absent or non-functional due to mutations in affected patients. Traditionally, such an approach requires a well characterized but arduous and expensive protein production procedure that employs in vitro expression and translation of the pharmaceutical protein in host cells, followed by extensive purification steps. In the wake of the SARS-CoV-2 pandemic, mRNA-based pharmaceuticals were recruited to achieve rapid in vivo production of antigens, proving that the in vivo translation of exogenously administered mRNA is nowadays a viable therapeutic option. In addition, the urgency of the situation and worldwide demand for mRNA-based medicine has led to an evolution in relevant technologies, such as in vitro transcription and nanolipid carriers. In this review, we present preclinical and clinical applications of mRNA as a tool for protein replacement therapy, alongside with information pertaining to the manufacture of modified mRNA through in vitro transcription, carriers employed for its intracellular delivery and critical quality attributes pertaining to the finished product.

COVID-19 vaccines adverse events: potential molecular mechanisms.

COVID-19 is an infectious disease caused by a single-stranded RNA (ssRNA) virus, known as SARS-CoV-2. The disease, since its first outbreak in Wuhan, China, in December 2019, has led to a global pandemic. The pharmaceutical industry has developed several vaccines, of different vector technologies, against the virus. Of note, among these vaccines, seven have been fully approved by WHO. However, despite the benefits of COVID-19 vaccination, some rare adverse effects have been reported and have been associated with the use of the vaccines developed against SARS-CoV-2, especially those based on mRNA and non-replicating viral vector technology. Rare adverse events reported include allergic and anaphylactic reactions, thrombosis and thrombocytopenia, myocarditis, Bell's palsy, transient myelitis, Guillen-Barre syndrome, recurrences of herpes-zoster, autoimmunity flares, epilepsy, and tachycardia. In this review, we discuss the potential molecular mechanisms leading to these rare adverse events of interest and we also attempt an association with the various vaccine components and platforms. A better understanding of the underlying mechanisms, according to which the vaccines cause side effects, in conjunction with the identification of the vaccine components and/or platforms that are responsible for these reactions, in terms of pharmacovigilance, could probably enable the improvement of future vaccines against COVID-19 and/or even other pathological conditions.

Serum Proteome Signatures of Anti-SARS-CoV-2 Vaccinated Healthcare Workers in Greece Associated with Their Prior Infection Status.

Over the course of the pandemic, proteomics, being in the frontline of anti-COVID-19 research, has massively contributed to the investigation of molecular pathogenic properties of the virus. However, data on the proteome on anti-SARS-CoV-2 vaccinated individuals remain scarce. This study aimed to identify the serum proteome characteristics of anti-SARS-CoV-2 vaccinated individuals who had previously contracted the virus and comparatively assess them against those of virus-naïve vaccine recipients. Blood samples of n = 252 individuals, out of whom n = 35 had been previously infected, were collected in the "G. Gennimatas" General Hospital of Thessaloniki, from 4 January 2021 to 31 August 2021. All participants received the BNT162b2 mRNA COVID-19 vaccine (Pfizer/BioNTech). A label-free quantitative proteomics LC-MS/MS approach was undertaken, and the identified proteins were analyzed using the GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes) databases as well as processed by bioinformatics tools. Titers of total RBD-specific IgGs against SARS-CoV-2 were also determined using the SARS-CoV-2 IgG II Quant assay. A total of 47 proteins were significantly differentially expressed, the majority of which were down-regulated in sera of previously infected patients compared to virus-naïve controls. Several pathways were affected supporting the crucial role of the humoral immune response in the protection against SARS-CoV-2 infection provided by COVID-19 vaccination. Overall, our comprehensive proteome profiling analysis contributes novel knowledge of the mechanisms of immune response induced by anti-SARS-CoV-2 vaccination and identified protein signatures reflecting the immune status of vaccine recipients.

S1P receptor modulators in Multiple Sclerosis: Detecting a potential skin cancer safety signal.

INTRODUCTION: S1P receptor modulators are oral Disease-Modifying Therapies (DMTs) for Multiple Sclerosis, which were associated with cases of basal cell carcinoma in clinical trials. This study aims at investigating in a real-world adverse event reporting system whether S1P receptor modulators increase the risk of skin cancer reporting, compared to other DMTs. METHODS: Adverse event reports from the FDA Adverse Event Reporting System (FAERS) were extracted, cleaned, and analyzed from 2004Q1 until 2020Q4. The crude and adjusted Reported Odds Ratios (cROR, aROR) for the outcomes: basal cell carcinoma, squamous cell carcinoma, or melanoma were calculated for all DMTs. In a sensitivity analysis, we looked at each outcome separately. RESULTS: The aROR (95%CI) of siponimod was: 9.68 (5.48-15.79) and of fingolimod 4.54 (3.86-5.32), indicating a safety signal of S1P receptor modulators for skin cancer. Ozanimod had only 52 complete reports without any cases. In the sensitivity analysis, siponimod showed a signal only for basal cell carcinoma: 22.83 (12.27-38.83), while fingolimod for all outcomes separately, including melanoma: 3.02 (2.31-3.89). Notably, among the other DMTs, alemtuzumab: 4.40 (2.98-6.25) and cladribine: 3.28 (1.17-7.13) presented also a signal for disproportionate reporting, while ocrelizumab showed a signal in the sensitivity analysis only for melanoma 2.55 (1.21-4.65). CONCLUSIONS: S1P receptors seem to increase skin cancer reporting on FAERS, and the association is strongest for basal cell carcinomas. Therefore, close dermatologic surveillance before- and during therapy is needed. Whether fingolimod and ocrelizumab also increase the risk of melanoma needs further investigation.

Antidepressants on Multiple Sclerosis: A Review of In Vitro and In Vivo Models.

Background: Increased prevalence of depression has been observed among patients with multiple sclerosis (MS) and correlated with the elevated levels of proinflammatory cytokines and the overall deregulation of monoaminergic neurotransmitters that these patients exhibit. Antidepressants have proved effective not only in treating depression comorbid to MS, but also in alleviating numerous MS symptoms and even minimizing stress-related relapses. Therefore, these agents could prospectively prove beneficial as a complementary MS therapy. Objective: This review aims at illustrating the underlying mechanisms involved in the beneficial clinical effects of antidepressants observed in MS patients. Methods: Through a literature search we screened and comparatively assessed papers on the effects of antidepressant use both in vitro and in vivo MS models, taking into account a number of inclusion and exclusion criteria. Results: In vitro studies indicated that antidepressants promote neural and glial cell viability and differentiation, reduce proinflammatory cytokines and exert neuroprotective activity by eliminating axonal loss. In vivo studies confirmed that antidepressants delayed disease onset and alleviated symptoms in Experimental Autoimmune Encephalomyelitis (EAE), the most prevalent animal model of MS. Further, antidepressant agents suppressed inflammation and restrained demyelination by decreasing immune cell infiltration of the CNS. Conclusion: Antidepressants were efficient in tackling numerous aspects of disease pathophysiology both in vitro and in vivo models. Given that several antidepressants have already proved effective in clinical trials on MS patients, the inclusion of such agents in the therapeutic arsenal of MS should be seriously considered, following an individualized approach to minimize the adverse events of antidepressants in MS patients.

The Effects of PDE Inhibitors on Multiple Sclerosis: a Review of in vitro and in vivo Models.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory and immune-mediated disease, whose current therapeutic means are mostly effective in the relapsing-remitting form of MS, where inflammation is still prominent, but fall short of preventing long term impairment. However, apart from inflammationmediated demyelination, autoimmune mechanisms play a major role in MS pathophysiology, constituting a promising pharmacological target. Phosphodiesterase (PDE) inhibitors have been approved for clinical use in psoriasis and have undergone trials suggesting their neuroprotective effects, rendering them eligible as an option for accessory MS therapy. OBJECTIVE: In this review, we discuss the potential role of PDE inhibitors as a complementary MS therapy. METHODS: We conducted a literature search through which we screened and comparatively assessed papers on the effects of PDE inhibitor use, both in vitro and in animal models of MS, taking into account a number of inclusion and exclusion criteria. RESULTS: In vitro studies indicated that PDE inhibitors promote remyelination and axonal sustenance, while curbing inflammatory cell infiltration, hindering oligodendrocyte and neuronal loss and suppressing cytokine production. In vivo studies underlined that these agents alleviate symptoms and reduce disease scores in MS animal models. CONCLUSION: PDE inhibitors proved to be effective in addressing various aspects of MS pathogenesis both in vitro and in vivo models. Given the latest clinical trials proving that the PDE4 inhibitor Ibudilast exerts neuroprotective effects in patients with progressive MS, research on this field should be intensified and selective PDE4 inhibitors with enhanced safety features should be seriously considered as prospective complementary MS therapy.

mRNA Therapeutic Modalities Design, Formulation and Manufacturing under Pharma 4.0 Principles.

In the quest for a formidable weapon against the SARS-CoV-2 pandemic, mRNA therapeutics have stolen the spotlight. mRNA vaccines are a prime example of the benefits of mRNA approaches towards a broad array of clinical entities and druggable targets. Amongst these benefits is the rapid cycle "from design to production" of an mRNA product compared to their peptide counterparts, the mutability of the production line should another target be chosen, the side-stepping of safety issues posed by DNA therapeutics being permanently integrated into the transfected cell's genome and the controlled precision over the translated peptides. Furthermore, mRNA applications are versatile: apart from vaccines it can be used as a replacement therapy, even to create chimeric antigen receptor T-cells or reprogram somatic cells. Still, the sudden global demand for mRNA has highlighted the shortcomings in its industrial production as well as its formulation, efficacy and applicability. Continuous, smart mRNA manufacturing 4.0 technologies have been recently proposed to address such challenges. In this work, we examine the lab and upscaled production of mRNA therapeutics, the mRNA modifications proposed that increase its efficacy and lower its immunogenicity, the vectors available for delivery and the stability considerations concerning long-term storage.

Circulatory effects of dexmedetomidine in early sepsis: a randomised controlled experimental study.

We designed this experimental study with a view to evaluate the effects of dexmedetomidine (DEX) on cardiac performance and systemic and peripheral hemodynamics in healthy and early-stage endotoxemia swine models. Our study hypothesis was that DEX can ensure hemodynamic stability during the course of endotoxemia. Thirty-two male pigs (25-27 kg) were assigned into four groups: (1) no intervention (group A), (2) DEX 0.8 µg/kg was administered in non-septic animals (group B), (3) sepsis induced by intravenous Escherichia coli endotoxin (group C) and (4) DEX 0.8 µg/kg was administered in septic animals (group D). Hemodynamic parameters such as heart rate, mean blood pressure, central venous pressure, pulmonary artery pressures, pulmonary artery occlusion pressure, pulmonary vascular resistance and cardiac output were continuously recorded. Central venous oxygen saturation was also measured in order to obtain a complete evaluation of cardiovascular response to sepsis. Heart rate was decreased, whilst mean arterial pressure decrease was alleviated after DEX administration in septic animals. In addition, central venous pressure was stable in animals with sepsis after DEX infusion. Sepsis dramatically elevated pulmonary function indicators but DEX succeeded in ameliorating this effect. The important decrease measured in central venous oxygen saturation in both sepsis groups reflected the decreased perfusion of tissues that takes place at the end of early sepsis. Our findings support the hypothesis that DEX has beneficial effects on heart rate and pulmonary artery pressure, whilst reduction in systemic blood pressure occurs at acceptable levels.

Dexmedetomidine effects in different experimental sepsis in vivo models.

Sepsis is a major cause of death and the most common cause of death among critically ill, non-ICU patients. Dexmedetomidine (DEX), an 2 adrenergic receptor agonist, presents sympatholytic action in certain parts of the brain with anxiolytic, sedative, and pain killing effects. Additionally, through the activation of 7 nicotinic acetylcholine receptor receptors, DEX reduces cytokine transcription and inhibits inflammation, rendering it beneficial during septic conditions. Moreover, there is a lot of interest in designing experimental sepsis models, where the administration of DEX is evaluated for its impact on multiple systems. This review focuses on experimental studies published between 1999 to March 2019 that were using DEX administration in sepsis in vivo models. From these, 36 articles were selected and summarized. Overall results show evidence that DEX may decrease mortality and inhibit inflammation, as it enhances the activity of the immune system while reducing its systemic reaction and lowering cytokine concentrations. Moreover DEX succeeds to alleviate heart injury during sepsis, acting beneficially for microcirculation and shows a neuroprotective role by inhibiting apoptotic pathways. In addition, DEX appears to have a protective role for liver and spleen as well as a beneficial role for the function of lungs and kidneys as it reduces sepsis-induced injuries and apoptosis in intra-abdominal experimental sepsis models.

Oxygen-Glucose Deprivation (OGD) Modulates the Unfolded Protein Response (UPR) and Inflicts Autophagy in a PC12 Hypoxia Cell Line Model.

Hypoxia is the lack of sufficient oxygenation of tissue, imposing severe stress upon cells. It is a major feature of many pathological conditions such as stroke, traumatic brain injury, cerebral hemorrhage, perinatal asphyxia and can lead to cell death due to energy depletion and increased free radical generation. The present study investigates the effect of hypoxia on the unfolded protein response of the cell (UPR), utilizing a 16-h oxygen-glucose deprivation protocol (OGD) in a PC12 cell line model. Expression of glucose-regulated protein 78 (GRP78) and glucose-regulated protein 94 (GRP94), key players of the UPR, was studied along with the expression of glucose-regulated protein 75 (GRP75), heat shock cognate 70 (HSC70), and glyceraldehyde 3-phosphate dehydrogenase, all with respect to the cell death mechanism(s). Cells subjected to OGD displayed upregulation of GRP78 and GRP94 and concurrent downregulation of GRP75. These findings were accompanied with minimal apoptotic cell death and induction of autophagy. The above observation warrants further investigation to elucidate whether autophagy acts as a pro-survival mechanism that upon severe and prolonged hypoxia acts as a concerted cell response leading to cell death. In our OGD model, hypoxia modulates UPR and induces autophagy.

Low Dose Administration of Glutamate Triggers a Non-Apoptotic, Autophagic Response in PC12 Cells.

BACKGROUND/AIMS: Increasing amounts of the neurotransmitter glutamate are associated with excitotoxicity, a phenomenon related both to homeostatic processes and neurodegenerative diseases such as multiple sclerosis. METHODS: PC12 cells (rat pheochromocytoma) were treated with various concentrations of the non-essential amino acid glutamate for 0.5-24 hours. The effect of glutamate on cell morphology was monitored with electron microscopy and haematoxylin-eosin staining. Cell survival was calculated with the MTT assay. Expression analysis of chaperones associated with the observed phenotype was performed using either Western Blotting at the protein level or qRT-PCR at the mRNA level. RESULTS: Administration of glutamate in PC12 cells in doses as low as 10 µM causes an up-regulation of GRP78, GRP94 and HSC70 protein levels, while their mRNA levels show the opposite kinetics. At the same time, GAPDH and GRP75 show reduced protein levels, irrespective of their transcriptional rate. On a cellular level, low concentrations of glutamate induce an autophagy-mediated pro-survival phenotype, which is further supported by induction of the autophagic marker LC3. CONCLUSION: The findings in the present study underline a discrete effect of glutamate on neuronal cell fate depending on its concentration. It was also shown that a low dose of glutamate orchestrates a unique expression signature of various chaperones and induces cell autophagy, which acts in a neuroprotective fashion.

Researching glutamate - induced cytotoxicity in different cell lines: a comparative/collective analysis/study.

Although glutamate is one of the most important excitatory neurotransmitters of the central nervous system, its excessive extracellular concentration leads to uncontrolled continuous depolarization of neurons, a toxic process called, excitotoxicity. In excitotoxicity glutamate triggers the rise of intracellular Ca(2+) levels, followed by up regulation of nNOS, dysfunction of mitochondria, ROS production, ER stress, and release of lysosomal enzymes. Excessive calcium concentration is the key mediator of glutamate toxicity through over activation of ionotropic and metabotropic receptors. In addition, glutamate accumulation can also inhibit cystine (CySS) uptake by reversing the action of the CySS/glutamate antiporter. Reversal of the antiporter action reinforces the aforementioned events by depleting neurons of cysteine and eventually glutathione's reducing potential. Various cell lines have been employed in the pursuit to understand the mechanism(s) by which excitotoxicity affects the cells leading them ultimately to their demise. In some cell lines glutamate toxicity is exerted mainly through over activation of NMDA, AMPA, or kainate receptors whereas in other cell lines lacking such receptors, the toxicity is due to glutamate induced oxidative stress. However, in the greatest majority of the cell lines ionotropic glutamate receptors are present, co-existing to CySS/glutamate antiporters and metabotropic glutamate receptors, supporting the assumption that excitotoxicity effect in these cells is accumulative. Different cell lines differ in their responses when exposed to glutamate. In this review article the responses of PC12, SH-SY5Y, HT-22, NT-2, OLCs, C6, primary rat cortical neurons, RGC-5, and SCN2.2 cell systems are systematically collected and analyzed.